As Singapore reopens its borders, more and more people travel abroad, and some even show their boarding passes on social media. But such a small action may leak your personal information at any time.

One TikTok user’s video especially, demonstrates how to use the boarding pass information to log in to other people’s airline accounts. They can then change their meals, seats, upgrades, and even cancel their tickets.

The TikTok user Jason Ho’s post on May 29th, warning social media users not to post pictures of boarding passes online has gone viral. He explains in the video that doing so would allow others to obtain personal information of passengers, including passport numbers, phone numbers and the last four digits of credit cards number.

He added that although those who are more cautious will block important information before publishing photos, those with malicious intent may still use other methods to obtain the required information.

Ho gave an example of a female internet celebrity who flew to the Vietnam SEA Games and posted her boarding pass online to illustrate his point. Although it was only 0.5 seconds, it was enough for him to get “all the information”.

To prove his point, he used a screenshot of the SIA boarding pass posted by the influencer, and then entered the 13-digit e-ticket number and the influencer’s surname on the SIA website, and the Passenger Name Record (PNR) was displayed. He showed how even receipts can be downloaded.

He also said that after logging in to her Singapore Airlines account, what he can do include changing or canceling her flight ticket, changing meals, changing seats, upgrading, etc. The personal information that can be obtained includes full name, passport number, passport validity period, The last four numbers of the credit card, date of birth, email address and mobile phone number.

He claimed to have contacted the influencer and informed her of the mistake.

Ho believes that most people upload photos of boarding passes purely to share the joy of traveling abroad, but he emphasised that if you want to upload photos of boarding passes, you should cover up all sensitive information, especially the e-ticket number.

As of May 30th, the video has gone viral with about 26,000 likes, more than 3,900 retweets and over 300 comments.

@coachjasonho PSA: Personal information hack #learningisfun #PSA #lifehacker #singaporeairlines #coachjasonho ♬ original sound – Coach Jason Ho

Many TikTok users who responded to him said that they did not know about the privacy issues caused by exposing the boarding pass when posting it on social media. Others suggested that airlines use two-factor authentication (2FA) or one-time password (OTP) to confirm the identity of passengers to protect their privacy.